It's been a blast playing this. I have enjoyed soloing all major boss battles (still annoyed at the copy-paste of lesser bosses-dammit Miyazaki-san!). I only used summons on two bosses as it was recommended to get more of the story/vibe. One being against Bayle the Dread, where I summoned [SPOIL]Igon[SPOIL], and they get to go all CURSE YOU, BAYLEEEEEEEE!
I used summons for the gank fight before the final boss fight because it's one against five NPCs who are all already challenging on their own, but as a group? Jesus-fuck-balls. If this was 1-on-1 against all five, I'm sure it would be a hoot, but as it is, it felt somewhat unfair.
Now all that is left is Radahn and Miquella. I'm enjoying the fight, even if I'm getting my teeth kicked over and over. :3
Cheers!